This invention relates to a vacuum cleaner dust bag comprising a collar of relatively rigid material and a dust container, fixed or detachably connected to the collar, which has an opening for an inlet tube of a vacuum cleaner hose, which conveys dust from the vacuum cleaner hose to its dust container, the opening being at least partly covered by an elastic diaphragm or the like having an aperture.
Dust bags of the above type are known. In these bags the object of the diaphragm is in the first place to close the opening so that dust collected in the bag will not escape from the bag when taken out of the vacuum cleaner. Another object of the diaphragm is to seal around the inlet tube, so that no air will leak around the inlet tube. Problems have arisen in the past in vacuum cleaners not having supporting plates for the collars of the known dust bags used therewith. Thus, the diaphragm of the known dust bag is not always capable of maintaining the collar on the inlet tube when the weight of the dust bag increases, after a certain period of use. When the bag has become detached from the inlet tube the dust and dirt therein will enter into the vacuum cleaner at the side of the bag.
The object of the present invention is to eliminate the above drawback, and to provide a dust bag which is safely retained to the inlet tube during the operation of the vacuum cleaner.
The above object of the invention is achieved in a dust bag wherein the shape of the opening is such that the inlet tube and a substantially nonresilient peripheral flange thereon, or a substantially nonresilient shoulder or shoulders on the inlet tube, can be moved through the opening without being significantly hindered by the surrounding collar. Furthermore, the collar, by being moved laterally or turned, can be brought to assume a blocking position in which the flange, shoulder or shoulders of the inlet tube prevents axial displacement of the collar.